The URL forwarding (WWW forwarding) feature that you can enable in the LoopiaDNS service is a redirection via frame, and is most easily compared to an HTML page that uses a frame, covering the entire page, which includes the destination address. You can reproduce the same behaviour yourself with an HTML page, as described below.
Replicating the forwarding with your own HTML file
The equivalent HTML code that we use is attached to this document. You only need to replace http://www.loopia.se/closed/ with the address you want to use instead.
Right-click on this link and select Save As index.html to save the file to your hard drive, then upload it to your public_html/ folder.
Address bar behaviour
Note that URL forwarding keeps the original domain name visible in the browser’s address bar, because the destination is loaded inside a frame. If you want the browser to show the destination URL instead, use URL redirection (HTTP 301/302) instead.